Rocket engines, such as those used to launch satellites, are costly to design and manufacture. At the same the demand for rocket engines capable of carrying payloads to space or near-Earth orbits continues to grow. Consequently, manufacturers of such rocket engines are constantly seeking new ways to reduce the design and manufacturing costs of producing rocket engine components.
One such component is the rocket thrust chamber within which the propellants of the rocket engine are combusted and accelerated. Because of the extremely high temperatures of the propellants moving through the thrust chamber, the walls of the thrust chamber must be cooled in those applications that require sustained engine firings. Such cooling is typically accomplished by flowing a coolant through tubes that form the inner wall of the thrust chamber. Since the manufacture of such thrust chambers is costly, novel ways of manufacturing such thrust chambers have been developed.
One example of the manufacture of such a thrust chamber is shown in U.S. Pat. No. 5,375,325 to Bales et al., which discloses a rocket chamber produced by positioning sleeved cooling tubes within a structural jacket to form a tube bundle, and positioning a liner within the tube bundle thereby sandwiching the tubes between the jacket and the liner. The tubes are then subjected to high internal pressure and inflated at high temperature while the liner is simultaneously subjected to the same high pressure, thereby forcing the sleeved tubes into intimate contact with adjacent sleeved tubes, the liner and the jacket. The temperature is maintained until bonding has occurred between the liner, sleeved tubes and jacket.
While the aforementioned patent represents an improvement over the prior art, the manufacture of the structural jacket which is used in the manufacture requires a great deal of machining, and each end of each of the tubes must be individually welded into manifold channels in the jacket. The time and effort associated with this machining and welding represents a significant portion of the manufacturing cost of the thrust chamber.
What is needed is a method of making a rocket thrust chamber requires less machining to form a structural jacket, and eliminates the need for each end of each of the tubes to be individually welded into manifold channels in the jacket.